1. Field of the Invention
The present invention relates to an apparatus and method for a wireless communication system. More particularly, the present invention relates to an apparatus and method for matching antenna impedance in a wireless communication system.
2. Description of the Related Art
The transmission efficiency of an antenna is affected by its input impedance. Accordingly, a transmitter typically performs impedance matching such that the reflective wave at the transmit antenna port may be minimized. However, the radiation impedance of the antenna varies depending on the surrounding environment, and appears very high at a frequency of 100 MHz or more.
In the case of a mobile station, the input impedance of its antenna varies significantly depending on the position of the user's hand that is holding the mobile station, and the manner in which the user grips the mobile station. The variation in the input impedance of the antenna causes a significant reduction in the transmit power that is actually output via the antenna.
In order to address these disadvantages and other problems, an antenna impedance matching method for minimizing the reflective wave has been used in the related art. However, to adopt this antenna impedance matching method, a component for calculating the reflection coefficient of the transmitter is additionally required. Undesirably, however, the use of the additional component may cause an increase in the manufacturing cost and make the antenna impedance matching process complicated. Accordingly, there is a need for an improved apparatus and method for matching antenna impedance in a wireless communication system.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present invention.